The Gasper River is a 38.6-mile-long (62.1 km)[1] river in southwestern Kentucky, USA. It flows northeasterly into the Barren River. It is a rural river; the only town near it is Hadley in Warren County. It begins in northeast Logan County, and the river also flows through Warren and Logan counties. Tributaries include Belcher, Salt Lick, Brush, Clear Fork, Westbrook, and Rock House creeks.

It is about 40 to 60 feet (12 to 18 m) wide and has a few small rapids. It is considered a mid-difficulty stream for canoeing.[2]

At the confluence with the Barren River is Sally's Rock, used as a river pilot's guide. It is named for Sally Beck, a local who delivered news to passing river boats in the 1880s.